Opacity 1.0

Opacity is a puzzle game played on an eight-by-eight grid. Four balls are randomly hidden somewhere on this grid, and it's your job to find them. Your only tools are beams that you can fire into the grid. These beams interact with the balls hidden on the grid, and you must determine where these balls are hidden using only the information about the beams' interactions. The rules are actually simple, but the results can be very complex.

Note: The "Download Now" link directs you to the iTunes App Store, where you must continue the download process. You must have iTunes installed in order to open the link, and you must have an active iTunes account to download the application. This download may not be available in some countries."